Lock and hill holder valve for hydraulic brakes



Dec. 30, 1952 A. B. SEPPMANN 2,523,541

LOCK AND HILL HOLDER VALVE FOR HYDRAULIC BRAKES Filed Nov. zo, 194s 2 SHEETS-SHEET 1 73 64 76 INVENTOR.. .f4 80 f zffedrymfm,

Dec. 30, 1952 A, B, SEPPMANN 2,623,541

LOCK AND HILL HOLDER VALVE FOR HYDRAULIC BRAKES Filed Nov. 2o, 194e 2 SHEETS-SHEET 2 F a7 f1 m f5: 11g 0 39 Illllllll i JNVENTOR. ifrdQ/D/va 71 71.

Patented Dec. 30, 1952 LOCK AND HILL HOLDER VALVE FOR HYDRAULIC BRAKES Alfred B. Seppmann, Mankato, Minn.

Application November 20, 1948, Serial No. 61,200

(Cl. ISL-598) Claims.

This invention relates to a means to lock the hydraulic brakes of an automobile, truck or the like in operated position by means of a push button control and to hold them in that position by means of another push button control, after which the second push button can be released, the brakes will remain in the applied position, the brakes being subsequently releasable by pushing the rst push button.

One object of the invention is to provide a simple arrangement for electrically operating a brake holder valve of a hydraulic brake system without the necessity of continuing the supply of current to the mechanism after the brakes are once set.

More specifically it is my object to provide a hydraulic valve structure to be interposed between the master cylinder and the brake iluid lines to the brakes of a vehicle, the valve being provided with means to operate the same and means to hold the same in operated position so that it can be released at will.

A further specic object is to provide a hydraulic valve which is normally open, and a solenoid for closing the valve, a second solenoid being provided to lock the valve in the closed position and being releasable by actuation of the rst solenoid, thereby simplifying the operations to those required for operating only a pair of push buttons in the proper sequence.

A further object is to provide a brake lock which is reliable in operation and a means to retain it in the locked position so that the brakes will hold of themselves on a hill without the necessity of keeping the brake pedal depressed, the mechanism being operable to readily release the brakes whenever desired.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings, wherein:

Figure 1 is a diagrammatic view of a hydraulic brake system with my invention applied thereto.

Figure 2 is an enlarged sectional view on the line 2 2 of Figure 1 showing a mounting for the push buttons that control the mechanism of my brake lock and hill holder.

Figure 3 is an enlarged vertical sectional view through the mechanism embodying my present invention and showing the parts in the normal or non-operated position.

Figures 4 and 5 are similar sectional views showing the parts in various operated positions.

Figures 6 and 7 are enlarged detail sectional views on the lines 6-6 of Figure 4 and 1--1 of Figure 5, respectively.

Figure 8 is an enlarged sectional view of a sleeve valve used in my mechanism, and

Figure 9 is a plan view of a gear shift lever with push buttons for controlling my mechanism mounted thereon.

On the accompanying drawings I have used the reference numeral I0 to indicate the steering column of an automobile, truck or the like and I2 the steering Wheel thereof. The front and rear brakes of the automobile are shown at I4 and I6 more or less diagrammatically and these brakes are of the hydraulic type having the usual actuating cylinders I8. The cylinders I 8 are ordinarily connected by piping 2Il with an outlet boss 22 of a master cylinder 24, the piston of the cylinder 24 being actuated by a brake pedal 26. The specic pipe of the brake fluid system that connects to the boss 22 is illustrated at 28 and this is cut somewhat shorter and connected to a fitting 3l) between which and the boss 22 I interpose my brake lock and hill holder assembly shown generally at A.

The assembly A comprises a hollow stud 32 having a head 34, the stud being threaded into the boss 22 of the master cylinder 24.` Interposed between the head 34 and suitably gasketed relative to the boss 22 is a sleeve 36 having a side outlet boss 38. lThe boss 38 receives a nipple 40 with which a plug 42 is connected, the plug extending into a sleeve 44 that forms the main body of my brake lock and hill holder valve. A tting 46 is screwed into the sleeve 44 and connects with the brake iluid pipe 2B as by means of a flare engaging plug 48 screwed into the iitting 46 against a are on the inner end of the pipe.

A sleeve valve 50 is slidable in a bore 52 of the plug 42 and is provided with ports 54, a metal seat 56 and a resilient seat 58 of neoprene or the like as best shown in Figure 8. The sleeve also has an annular valve lip 60 surrounding a passageway 59 through the valve. The seats 56 and 58 are adapted to engage a seat 62 of the plug 42 under the bias of a spring 64. A plug 66 is located inr the plug 42 and is removable for gaining access to the sleeve valve 50.

A solenoid plunger 68 is slidable in the valve body 44 and is normally biased to the rearward or right hand position of Figure 3 by the spring 64. The plunger is provided with grooves 69 and holes 69a extending longitudinally through it (see Figure 7). It carries a stem 'I0 slidable relative to the plunger and having a valve plug l2 on its forward end and a head I4 on its rear end provided with perforations 14a and radial grooves 74h. A light spring 'I6 is interposed between the valve head I2 and the plunger 68 to normally bias the head I2 toward the valve lip 60. The head 'l2 has a resilient disc-like insert 'I8 for engagement at times with the valve lip.

A solenoid coil Si) surrounds the valve body 44 in an appropriate position for pulling the plunger 68 toward the left when the coil is energized.

One end of the coil is grounded and its other end is connected by a Wire 82 to a push button 84 which in Figure l I have labeled L The push button @il is mounted in a housing 86 which may be secured to the steering column ID by clamp plates S8 and a clamp screw Sii. nstead of the steering column, the push buttons may be mounted on the dash (not shown) or on the gear shift lever S2 as shown in Figure 9 and as will hereinafter be described.

Current is supplied to the push button 8d by a wire @il extending from the starting and lighting battery 9% of the vehicle. One side of this battery b-eing grounded in the usual manner so as to complete the circuit to the grounded end of the solenoid coil SB.

A second solenoid coil 98 is mounted on a fitting lili] screwed into the side of the valve body 44 and a plunger m2 is mounted therein and normally biased to the raised position shown in Figure 3 by a spring idd. The plunger has a downwardly extending stem it terminating in a head |538 which is adapted to assume a position back of the plunger (it as in Figure 5 when the coil $38 is energized. The plunger @S has a cylindrical flange i I@ to engage the head m8 at times as will hereinafter appear.

The solenoid coil 98 is adapted to be energized when current is conducted to it by a wire H2 extended to a second push button lit mounted in the housing it and labeled 2. This push button likewise has its other terminal connected with the wire Qt.

In Figure 9 I show a. modification wherein the push button et is mounted in a knob e3 of a lgear shift lever Q2 and the push button l i4 is mounted in a housing Si secured to the gear shift lever as by a strap 3S. A bell crank lever 89a is pivoted to a bracket 9i of the housing lil for convenience in operating the push button Ht. This type of installation is also suitable for the upper end of that type of gear shift lever which extends upwardly from the door boards of the vehicle.

Practical operation En the operation of my device the parts are normally in the position of Figure 3 and in no way interfere with the normal operation of the brakes. When the brake pedal 25 is depressed brake fiuid from the master cylinder 24 flows through the nipple du and opens the sleeve valve 5; against the action of the spring G4 in much the saine manner as any check valve is opened. Some of the iiuid will flow through the passageway te of the sleeve valve 5i! itself and issue from i the valve lip Sli.

The longitudinal grooves Gil and holes G9a. of the plunger 53 permit the fluid to flow freely past it and the perforations and radial grooves 'ida and "zflh in the head M also permit free flow of the fluid into the fitting dii. When the brake pedal is released the valve seats d6 and 53 will engage the valve seat S2 and the brake nuid will return through the passageway 59 of the sleeve valve Sii.

In the event that it is desirable to lock the brakes in applied or set position, the brake pedal is depressed for setting the brakes and then first push button 5d is depressed which moves the plunger 68 forwardly to the position ci Figure 4 causing the valve disc 'I3 to seat against the lip @il and seal the brake fluid against return now even when the brake pedal is released. This locked condition will obtain as long as the first push button is held depressed 4 and the brakes will be released when the push button is released.

There are many instances, as when stopping on a hill, that it is desirable to hold the brakes in the applied position and it is desirable to do this without having to hold the push button 84 depressed. Also it is undesirable to energize the solenoid 8a for too long a period of time because of undue heating of the coil and excessive drain on the battery 95.

I therefore provide the second solenoid 9B which may be operated after the first push button is depressed by depressing the second one H4. rIhis causes the stem IBG and its head l to be moved downwardly from the position of Figure 4 to the position of Figure 5 but the plunger Si remains in the position of Figure 4 until the first push button gli is released after depressing the second push button. rThereupon the plunger 63 is moved rearwardly due to the action of the spring 64 and the flange Il@ engages over the head i G8 of the plunger iiiZ so that when the second push button is released the spring we cannot return the plunger upwardly.

This leaves the valve Bil-F8 locked closed as the spring 16 expands slightly to keep these parts engaged when the plunger 63 moves from the position of Figure 4 to the position of Figure 5. Accordingly the brakes will be held in the applied position as long as the parts remain in the position shown in Figure 5.

When it is desirable to subsequently release the brakes, the first push button 84 is depressed which again moves the plunger 68 forwardly as to the position of Figure 4, thus releasing the plunger I2 so that it is returned upwardly as in Figure 4 by the spring 104. Then when the rst push button 84 is released again the plunger 68 moves to the position of Figure 3 for releasing the brakes, the brake duid then of course returning through the passageway 59 in th-e sleeve valve 5U to the master cylinder.

An important feature of my construction reysides in the design of the plunger 68 so that it must travel some distance from the position of Figure 3 before the valve 60--18 closes in a position intermediate those positions illustrated in Figures 3 and 4 under action of the spring 16.

j There is then further movement of the plunger while the space is taken up between its forward end and the back of the valve plug 12, the spring 16 all during such further movement keeping the valve parts 60 and 'H3 engaged. Finally the forward end of the plunger 68 strikes the valve 'plug 12 as in Figure 4 and this imparts a hammer blow to effect the final seating of the valve 60-18 and also effects a hammer blow of the valve seats 56 and 58 which are normally seated under the action of the spring 64, against the seat 62 to insure holding the brake uid against any possible return to the master cylinder While my lock and hill holder valve is in holding position.

Comparing Figure 8 with Figure 3 it will be noted that the resilient 'seat 58 has a different shape and this results in it seating first and thereafter the metal seat 56 seating against 62 which prevents the entire load being put on the resilient seat 58 which would soon cause it to crush down and require renewal. This two-stage seating accordingly lengthens the life of this valve many fold and is an important feature of the valve along with the hammer-action for seating the valve. Likewise when the valve is opened the plunger 68 will gain momentum under the action of the spring 64 until its rear end hammers against the head T4 for effecting an unseating at 69-18 with a force much greater th-an otherwise. I am thereby assured of positive seating and unseating due to the hammer-action while at the same time a relatively small solenoid coil 8U is sufficient for the purpose and entails less current drain than most types of coils used for this purpose.

My arrangement also eliminates the necessity of keeping a solenoid energ'ized for an excessive period of time and this is accomplished by the second solenoid which need not be very large Ias it actuates only the plunger |02 instead of a hydraulic valve as in the case of the plunger 88.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modied forms of structure or use of mechanical equivalents wh'ich may be reasonably included within their scope.

'I claim as my invention:

1. In a brake control device, -a valve between a ina-ster cylinder and a brake uid line, a plunger having a lost motion connection with said valve for closing it with hammer action, a spring for returning said plunger from valve-closed position, said -plunger having a recessed shoulder, a second plunger for locking said rst plunger against return movement, a second spring for returning said second plunger lfrom first plungerlocking position, the recess of said shoulder of `said. iirst plunger being engagea'ble with said second plunger to lool; it against return movement by said second spring when said first plunger partially returns after being moved to close said valve, and to unlock said second plunger when said rst plunger i-s moved again in the valve-clos ing direction, and a manual control for each of said plungers to move them in opposition to their -i return springs.

2. In a hydraulic brake control device, a valve for interposition between a master cylinder and a brake fluid line, a rst plunger for closing said valve, a rst spring for returning said first plunger for opening said valve, said first plunger having a recessed shoulder, a second plunger for engaging behind said -shoulder for thereby locking said first plunger against return movement, a second spring for returning said second plunger to unlock said first plunger, the recess of said shoulder of said rst plunger being engageable under action of said rst spring with said second plunger to lock it against return movement by said second spring when said :first plunger partially returns after being moved to close said valve, said shoulder of said rst plunger dis-engaging said second plunger when the first plunger is moved again in the valve closing direction, and means for moving each of said plungers in opposition to their spring returned directions of movement.

3. In a brake lock and hill holder device, a valve body, a valve therein adapted to be unseated when brake fluid flows therethrough to the brakes and to be seated upon reverse flow, a passageway therethrough to permit reverse flow of fluid, a pair of solenoid coils, a valve element adapted for seating on said passageway, a plunger having a lost motion connection with said valve element to close it against said passageway when one of said solenoid coils is energized, means to bias said first plunger to return from valve-closing position, saidV plunger having a shoulder, a second plunger for positioning back of said shoulder and thereby locking said first plunger in the closed -position of said valve element relative to said passageway, said second solenoid coil actuating said second plunger to such position, means biasing said second plunger to return from its locking position, said shoulder of said rst plunger being 'recessed to engage said second plunger and lock it against retraction when said first solenoid coil is `dee-energized following energization thereof, and means for cont-rolling the supply of current to each of said solenoids independently and 'in the desired sequence.

4. In a brake lock and hill holder of the character disclosed, a valve unit adapted to be iriterposed between a master cylinder and a brake fluid line comprising a valve seat and a valve element which permits normal flow of brake uid in both directions through said valve seat when said valve element is spaced therefrom and prevents such ilow when said valve element is seated thereon, a 'solenoid having a plunger for seating said valve element when said rst solenoid is energized, a spring for -returning said plunger when said first solenoid is de-energized, said plunger having a spring extended, lost motion connection with said valve element for seating it with hammer action, a second solenoid having a second plunger for locking said rst plunger in valveclosed position when said second solenoid is energized following energization of said first solenoid, a second spring for returning said second plunger when said second solenoid is dia-energized, said rst plunger engaging said second plunger when said rstsolenoid is de-energized and while said second solenoid is energized to hold said first plunger against return movement as long as both of said solenoids then remain de-energized, said first plunger when the rst solenoid is re-energized, disengaging said second plunger -to permit it to be spring returned from its locking position with respect to said first plunger.

5. In a valve structure of the character disclosed, a unit adapted to be interposed between a master cylinder anda brake fluid line comprising a valve seat and a valve element which permits normal flow of brake fluid in both directions through said valve seat when said valve element is spaced therefrom and prevents such flow when said valve element is seated thereon, a first solenoid having a plunger for seating said valve element when said first solenoid is energized, a spring for returning said plunger when said rst solenoid is de-energized, a, second solenoid having a second plunger for locking said first plunger in valve-closed position when said second solenoid is energized, a second spring for returning said second plunger when said second solenoid is deenergized, said first plunger upon being spring returned after said first solenoid is de-energized yand while said second solenoid is energized engaging said second plunger to hold it against return movement by its return spring as long as said first solenoid remains dez-energized.

ALFRED B. SEPPMANN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 775,054 Waterman Nov. 15, 1904 1,924,251 McGuire Aug. 29, 1933 2,220,465 Spotz Nov. 5, 1940 

